Jaspers's view of the relationship between philosophy and religion is neatly conveyed by the following sentence from the first volume of his Philosophie (English translation: Philosophy) of 1932: “The philosophical-religious tension is absolute; a genuinely religious person may become a theologian, but without an inner break he cannot become a philosopher, and the philosopher as such cannot without such a break become a religious person.” Jaspers maintains this view into his later writings. Toward the end of his last great work, Der philosophische Glaube angesichts der Offenbarung (English translation: Philosophical Faith and Revelation) of 1962, he quotes a statement by Arthur Schopenhauer in his handwritten papers, which was probably the model for the sentence just quoted from Philosophy: “No one who is religious comes to philosophy; he does not need it. No one who really philosophizes is religious; he walks without leading strings, dangerously, but in freedom.” From this point of view, it is in a certain way understandable that theologians usually react quite “allergically” to Jaspers and prefer to turn to Heidegger, whose “methodical atheism” is less objectionable to theology.

Thus, although philosophy and religion are, according to Jaspers, mutually exclusive, he repeatedly dealt with them in his work in the context of the “philosophical faith” he developed. In his “Philosophische Autobiographie” (English translation: “Philosophical Autobiography”) he explains this as follows: “When I began to philosophize, it never occurred to me that I could ever become interested in theology.” Growing up in a Protestant family that ignored the church, Jaspers developed little relationship with church religion. However, he soon realized that the reality of the church and theology cannot be neglected in philosophizing. In this context, he recounts a strange experience: